Spatio-temporal structure and reproductive success in a rook (Corvus frugilegus) colony

  • Miklós Bán MTA-DE Behavioural Ecology Research Group, Department of Evolutionary Zoology and Human Biology, University of Debrecen, H-4010 Debrecen, Egyetem tér 1, Hungary https://orcid.org/0000-0002-6275-7928
  • Orsolya Feró MTA-DE “Lendület” Genome Architecture and Recombination Laboratory University of Debrecen, H-4010 Debrecen, Egyetem tér 1, Hungary https://orcid.org/0000-0001-8052-9948
  • Zoltán Barta MTA-DE “Lendület” Genome Architecture and Recombination Laboratory University of Debrecen, H-4010 Debrecen, Egyetem tér 1, Hungary https://orcid.org/0000-0002-7121-9865
Keywords: Corvus frugilegus, coloniality, colony structure, colony formation, breeding success, clutch size, hatching success, nest density, nest site selection, colony syncrony

Abstract

We have studied how individual decisions about timing of breeding and nest location affected the reproductive success of rooks by tracing the formation of a rook breeding colony in Hortobágy NP (Hungary), during the breeding season in 1999.

We have found that birds who built nests earlier also laid eggs earlier and had larger clutch size but had no more offspring than late nesters. Distance of the nest from the centre or edge of the colony did not affect the reproductive success though rooks generally settled closer to the centre and further from the edge than it can be expected by assuming random distribution. The colony showed high breeding synchrony since date of egg laying varied less than date of nesting but synchrony did not influence the breeding success. Hatchling's survival rate and number of offspring increased with local nest density and rooks clustered their nests more than it can be expected by random settlement. Nest sites of early and late nesters did not differ regarding the distance from the centre or the edge of the colony but late nesters chose nest sites in more densely populated regions.

The results indicate that individuals may follow different strategies to increase their reproductive success. It is prospectively advantageous to build the nest and lay eggs earlier, in turn, it's worth nesting in already more densely nested areas for late beginners. We suggest that a game theoretical approach may be useful if we try to understand the adaptive significance of colonial breeding.

Published
2019-04-04
How to Cite
BánM., FeróO., & BartaZ. (2019). Spatio-temporal structure and reproductive success in a rook (Corvus frugilegus) colony. Acta Zoologica Academiae Scientiarum Hungaricae, 65(1). https://doi.org/10.17109/AZH.65.1.31.2019